Non-http/https URLS?

I was editing a page on my Ghost 5.31.0 community organization site, and I wanted to put some mailto: and tel: links for emails and telephone numbers. I noticed that the [link title](url) format doesn’t seem to recognize either mailto: or tel: links, that make an email address or telephone number clickable. I could see this for any protocol, not just http, https, or these two new ones. Let the browser decide how to handle any protocol (basically, make the (url) be a URI).

I resorted to having a raw HTML card with anchors in them, but that’s a lot of extra HTML code for something so simple.